Background and Objectives : The nasalance score measured by Nasometer is a supplementary data for the perceptually rated nasality by a trained speech pathologist. The nasalance score varies with subjects. The objective of the present study was to examine whether there are differences in nasalance scores as a function of age and sex. Materials and Method : This study used 20 normal chidren aged from 3 to 8 and 40 normal adults aged from 21 to 37(male : female= 1 : 1) as subjects. The nasalance scores were analyzed in 3 different phonetic contests(nasal, /i/ vowel,/a/ vowel) and 4 different sentence lengths(1, 2, 4, 8 syllable). Results : The children had significantly higher nasalance scores in short sentences an the adults. The female subjects had significantly higher nasalance scores in nasal sentences and in short sentences than the male subjects. Conclusion : These results may indicate that sex and age differences should be considered in the interpretation of the nasalance score in nasal sentences or in short sentences.